The development of effective pharmacological treatment strategies for cocaine abuse will depend on a better understanding of the effects of cocaine on brain neurochemistry and central nervous system function. The current project utilized positron emission tomography (PET) imaging techniques in nonhuman primates as an innovative, non-invasive approach to investigate cocaine-induced functional changes in central nervous system activity. The results obtained during the first year of the project have shown robust and reliable dose-dependent changes in the pattern of regional cerebral blood flow following cocaine administration in awake monkeys. Ongoing research will continue to focus on the acute effects of cocaine in subjects with a documented history of cocaine use under well-controlled laboratory conditions. Once validated, the model can provide a technical and theoretical framework for screening pharmacotherapies in the treatment of cocaine addiction.